fix: dispose TextEditingControllers in settings dialogs

lib/main.dart

@@ -397,7 +397,7 @@ class _MainAppState extends State<MainApp> with WidgetsBindingObserver {
       case AppLifecycleState.paused:
       case AppLifecycleState.detached:
         if (Platform.isAndroid || Platform.isIOS) {
-          _appDatabase.close();
+          unawaited(_appDatabase.close());
         }
         InAppReviewService.instance.endSession();
         if (Platform.isWindows || Platform.isMacOS || Platform.isLinux) {

lib/screens/settings/settings_screen.dart

@@ -578,7 +578,10 @@ class _SettingsScreenState extends State<SettingsScreen> with FocusableTab {
           ],
         );
       },
-    ).then((_) => saveFocusNode.dispose());
+    ).then((_) {
+      controller.dispose();
+      saveFocusNode.dispose();
+    });
   }
 
   void _showClearCacheDialog() {

lib/screens/settings/settings_utils.dart

@@ -220,6 +220,7 @@ void _showNumericInputDialogStandard({
       );
     },
   ).then((_) {
+    controller.dispose();
     saveFocusNode.dispose();
   });
 }
@@ -286,5 +287,8 @@ void showTextInputDialog({
         },
       );
     },
-  ).then((_) => saveFocusNode.dispose());
+  ).then((_) {
+    controller.dispose();
+    saveFocusNode.dispose();
+  });
 }